# uncompyle6 version 3.2.3
# Python bytecode 3.6 (3379)
# Decompiled from: Python 3.6.8 |Anaconda custom (64-bit)| (default, Feb 21 2019, 18:30:04) [MSC v.1916 64 bit (AMD64)]
# Embedded file name: lib2to3\refactor.py
"""Refactoring framework.

Used as a main program, this can refactor any number of files and/or
recursively descend down directories.  Imported as a module, this
provides infrastructure to write your own refactoring tool.
"""
__author__ = "Guido van Rossum <guido@python.org>"
import os, sys, logging, operator, collections, io
from itertools import chain
from .pgen2 import driver, tokenize, token
from .fixer_util import find_root
from . import pytree, pygram
from . import btm_matcher as bm


def get_all_fix_names(fixer_pkg, remove_prefix=True):
    """Return a sorted list of all available fix names in the given package."""
    pkg = __import__(fixer_pkg, [], [], ["*"])
    fixer_dir = os.path.dirname(pkg.__file__)
    fix_names = []
    for name in sorted(os.listdir(fixer_dir)):
        if name.startswith("fix_"):
            if name.endswith(".py"):
                if remove_prefix:
                    name = name[4:]
                fix_names.append(name[:-3])

    return fix_names


class _EveryNode(Exception):
    pass


def _get_head_types(pat):
    """ Accepts a pytree Pattern Node and returns a set
    of the pattern types which will match first. """
    if isinstance(pat, (pytree.NodePattern, pytree.LeafPattern)):
        if pat.type is None:
            raise _EveryNode
        return {pat.type}
    if isinstance(pat, pytree.NegatedPattern):
        if pat.content:
            return _get_head_types(pat.content)
        raise _EveryNode
    if isinstance(pat, pytree.WildcardPattern):
        r = set()
        for p in pat.content:
            for x in p:
                r.update(_get_head_types(x))

        return r
    raise Exception("Oh no! I don't understand pattern %s" % pat)


def _get_headnode_dict(fixer_list):
    """ Accepts a list of fixers and returns a dictionary
    of head node type --> fixer list.  """
    head_nodes = collections.defaultdict(list)
    every = []
    for fixer in fixer_list:
        if fixer.pattern:
            try:
                heads = _get_head_types(fixer.pattern)
            except _EveryNode:
                every.append(fixer)

            for node_type in heads:
                head_nodes[node_type].append(fixer)

        elif fixer._accept_type is not None:
            head_nodes[fixer._accept_type].append(fixer)
        else:
            every.append(fixer)

    for node_type in chain(
        pygram.python_grammar.symbol2number.values(), pygram.python_grammar.tokens
    ):
        head_nodes[node_type].extend(every)

    return dict(head_nodes)


def get_fixers_from_package(pkg_name):
    """
    Return the fully qualified names for fixers in the package pkg_name.
    """
    return [
        pkg_name + "." + fix_name for fix_name in get_all_fix_names(pkg_name, False)
    ]


def _identity(obj):
    return obj


if sys.version_info < (3, 0):
    import codecs

    _open_with_encoding = codecs.open

    def _from_system_newlines(input):
        return input.replace("\r\n", "\n")

    def _to_system_newlines(input):
        if os.linesep != "\n":
            return input.replace("\n", os.linesep)
        else:
            return input


else:
    _open_with_encoding = open
    _from_system_newlines = _identity
    _to_system_newlines = _identity


def _detect_future_features(source):
    have_docstring = False
    gen = tokenize.generate_tokens(io.StringIO(source).readline)

    def advance():
        tok = next(gen)
        return (tok[0], tok[1])

    ignore = frozenset({token.NEWLINE, tokenize.NL, token.COMMENT})
    features = set()
    try:
        while True:
            tp, value = advance()
            if tp in ignore:
                continue
            elif tp == token.STRING:
                if have_docstring:
                    break
                have_docstring = True
            elif tp == token.NAME and value == "from":
                tp, value = advance()
                if tp != token.NAME or value != "__future__":
                    break
                tp, value = advance()
                if tp != token.NAME or value != "import":
                    break
                tp, value = advance()
                if tp == token.OP:
                    if value == "(":
                        tp, value = advance()
                while tp == token.NAME:
                    features.add(value)
                    tp, value = advance()
                    if tp != token.OP or value != ",":
                        break
                    tp, value = advance()

            else:
                break

    except StopIteration:
        pass

    return frozenset(features)


class FixerError(Exception):
    """A fixer could not be loaded."""

    pass


class RefactoringTool(object):
    _default_options = {"print_function": False, "write_unchanged_files": False}
    CLASS_PREFIX = "Fix"
    FILE_PREFIX = "fix_"

    def __init__(self, fixer_names, options=None, explicit=None):
        """Initializer.
        
        Args:
            fixer_names: a list of fixers to import
            options: a dict with configuration.
            explicit: a list of fixers to run even if they are explicit.
        """
        self.fixers = fixer_names
        self.explicit = explicit or []
        self.options = self._default_options.copy()
        if options is not None:
            self.options.update(options)
        if self.options["print_function"]:
            self.grammar = pygram.python_grammar_no_print_statement
        else:
            self.grammar = pygram.python_grammar
        self.write_unchanged_files = self.options.get("write_unchanged_files")
        self.errors = []
        self.logger = logging.getLogger("RefactoringTool")
        self.fixer_log = []
        self.wrote = False
        self.driver = driver.Driver(
            self.grammar, convert=pytree.convert, logger=self.logger
        )
        self.pre_order, self.post_order = self.get_fixers()
        self.files = []
        self.BM = bm.BottomMatcher()
        self.bmi_pre_order = []
        self.bmi_post_order = []
        for fixer in chain(self.post_order, self.pre_order):
            if fixer.BM_compatible:
                self.BM.add_fixer(fixer)
            elif fixer in self.pre_order:
                self.bmi_pre_order.append(fixer)
            elif fixer in self.post_order:
                self.bmi_post_order.append(fixer)

        self.bmi_pre_order_heads = _get_headnode_dict(self.bmi_pre_order)
        self.bmi_post_order_heads = _get_headnode_dict(self.bmi_post_order)

    def get_fixers(self):
        """Inspects the options to load the requested patterns and handlers.
        
        Returns:
          (pre_order, post_order), where pre_order is the list of fixers that
          want a pre-order AST traversal, and post_order is the list that want
          post-order traversal.
        """
        pre_order_fixers = []
        post_order_fixers = []
        for fix_mod_path in self.fixers:
            mod = __import__(fix_mod_path, {}, {}, ["*"])
            fix_name = fix_mod_path.rsplit(".", 1)[-1]
            if fix_name.startswith(self.FILE_PREFIX):
                fix_name = fix_name[len(self.FILE_PREFIX) :]
            parts = fix_name.split("_")
            class_name = self.CLASS_PREFIX + ("").join([p.title() for p in parts])
            try:
                fix_class = getattr(mod, class_name)
            except AttributeError:
                raise FixerError("Can't find %s.%s" % (fix_name, class_name))

            fixer = fix_class(self.options, self.fixer_log)
            if fixer.explicit:
                if self.explicit is not True:
                    if fix_mod_path not in self.explicit:
                        self.log_message("Skipping optional fixer: %s", fix_name)
                        continue
                self.log_debug("Adding transformation: %s", fix_name)
                if fixer.order == "pre":
                    pre_order_fixers.append(fixer)
                elif fixer.order == "post":
                    post_order_fixers.append(fixer)
                else:
                    raise FixerError("Illegal fixer order: %r" % fixer.order)

        key_func = operator.attrgetter("run_order")
        pre_order_fixers.sort(key=key_func)
        post_order_fixers.sort(key=key_func)
        return (pre_order_fixers, post_order_fixers)

    def log_error(self, msg, *args, **kwds):
        """Called when an error occurs."""
        raise

    def log_message(self, msg, *args):
        """Hook to log a message."""
        if args:
            msg = msg % args
        self.logger.info(msg)

    def log_debug(self, msg, *args):
        if args:
            msg = msg % args
        self.logger.debug(msg)

    def print_output(self, old_text, new_text, filename, equal):
        """Called with the old version, new version, and filename of a
        refactored file."""
        pass

    def refactor(self, items, write=False, doctests_only=False):
        """Refactor a list of files and directories."""
        for dir_or_file in items:
            if os.path.isdir(dir_or_file):
                self.refactor_dir(dir_or_file, write, doctests_only)
            else:
                self.refactor_file(dir_or_file, write, doctests_only)

    def refactor_dir(self, dir_name, write=False, doctests_only=False):
        """Descends down a directory and refactor every Python file found.
        
        Python files are assumed to have a .py extension.
        
        Files and subdirectories starting with '.' are skipped.
        """
        py_ext = os.extsep + "py"
        for dirpath, dirnames, filenames in os.walk(dir_name):
            self.log_debug("Descending into %s", dirpath)
            dirnames.sort()
            filenames.sort()
            for name in filenames:
                if not name.startswith("."):
                    if os.path.splitext(name)[1] == py_ext:
                        fullname = os.path.join(dirpath, name)
                        self.refactor_file(fullname, write, doctests_only)

            dirnames[:] = [dn for dn in dirnames if not dn.startswith(".")]

    def _read_python_source(self, filename):
        """
        Do our best to decode a Python source file correctly.
        """
        try:
            f = open(filename, "rb")
        except OSError as err:
            self.log_error("Can't open %s: %s", filename, err)
            return (None, None)

        try:
            encoding = tokenize.detect_encoding(f.readline)[0]
        finally:
            f.close()

        with _open_with_encoding(filename, "r", encoding=encoding) as (f):
            return (_from_system_newlines(f.read()), encoding)

    def refactor_file(self, filename, write=False, doctests_only=False):
        """Refactors a file."""
        input, encoding = self._read_python_source(filename)
        if input is None:
            return
        input += "\n"
        if doctests_only:
            self.log_debug("Refactoring doctests in %s", filename)
            output = self.refactor_docstring(input, filename)
            if self.write_unchanged_files or output != input:
                self.processed_file(output, filename, input, write, encoding)
            else:
                self.log_debug("No doctest changes in %s", filename)
        else:
            tree = self.refactor_string(input, filename)
            if self.write_unchanged_files or tree and tree.was_changed:
                self.processed_file(
                    str(tree)[:-1], filename, write=write, encoding=encoding
                )
            else:
                self.log_debug("No changes in %s", filename)

    def refactor_string(self, data, name):
        """Refactor a given input string.
        
        Args:
            data: a string holding the code to be refactored.
            name: a human-readable name for use in error/log messages.
        
        Returns:
            An AST corresponding to the refactored input stream; None if
            there were errors during the parse.
        """
        features = _detect_future_features(data)
        if "print_function" in features:
            self.driver.grammar = pygram.python_grammar_no_print_statement
        try:
            tree = self.driver.parse_string(data)
        except Exception as err:
            self.log_error("Can't parse %s: %s: %s", name, err.__class__.__name__, err)
            return
        finally:
            self.driver.grammar = self.grammar

        tree.future_features = features
        self.log_debug("Refactoring %s", name)
        self.refactor_tree(tree, name)
        return tree

    def refactor_stdin(self, doctests_only=False):
        input = sys.stdin.read()
        if doctests_only:
            self.log_debug("Refactoring doctests in stdin")
            output = self.refactor_docstring(input, "<stdin>")
            if self.write_unchanged_files or output != input:
                self.processed_file(output, "<stdin>", input)
            else:
                self.log_debug("No doctest changes in stdin")
        else:
            tree = self.refactor_string(input, "<stdin>")
            if self.write_unchanged_files or tree and tree.was_changed:
                self.processed_file(str(tree), "<stdin>", input)
            else:
                self.log_debug("No changes in stdin")

    def refactor_tree(self, tree, name):
        """Refactors a parse tree (modifying the tree in place).
        
        For compatible patterns the bottom matcher module is
        used. Otherwise the tree is traversed node-to-node for
        matches.
        
        Args:
            tree: a pytree.Node instance representing the root of the tree
                  to be refactored.
            name: a human-readable name for this tree.
        
        Returns:
            True if the tree was modified, False otherwise.
        """
        for fixer in chain(self.pre_order, self.post_order):
            fixer.start_tree(tree, name)

        self.traverse_by(self.bmi_pre_order_heads, tree.pre_order())
        self.traverse_by(self.bmi_post_order_heads, tree.post_order())
        match_set = self.BM.run(tree.leaves())
        while any(match_set.values()):
            for fixer in self.BM.fixers:
                if fixer in match_set and match_set[fixer]:
                    match_set[fixer].sort(key=pytree.Base.depth, reverse=True)
                    if fixer.keep_line_order:
                        match_set[fixer].sort(key=pytree.Base.get_lineno)
                    for node in list(match_set[fixer]):
                        if node in match_set[fixer]:
                            match_set[fixer].remove(node)
                        try:
                            find_root(node)
                        except ValueError:
                            continue

                        if node.fixers_applied:
                            if fixer in node.fixers_applied:
                                continue
                            results = fixer.match(node)
                            if results:
                                new = fixer.transform(node, results)
                                if new is not None:
                                    node.replace(new)
                                    for node in new.post_order():
                                        if not node.fixers_applied:
                                            node.fixers_applied = []
                                        node.fixers_applied.append(fixer)

                                    new_matches = self.BM.run(new.leaves())
                                    for fxr in new_matches:
                                        if fxr not in match_set:
                                            match_set[fxr] = []
                                        match_set[fxr].extend(new_matches[fxr])

        for fixer in chain(self.pre_order, self.post_order):
            fixer.finish_tree(tree, name)

        return tree.was_changed

    def traverse_by(self, fixers, traversal):
        """Traverse an AST, applying a set of fixers to each node.
        
        This is a helper method for refactor_tree().
        
        Args:
            fixers: a list of fixer instances.
            traversal: a generator that yields AST nodes.
        
        Returns:
            None
        """
        if not fixers:
            return
        for node in traversal:
            for fixer in fixers[node.type]:
                results = fixer.match(node)
                if results:
                    new = fixer.transform(node, results)
                    if new is not None:
                        node.replace(new)
                    node = new

    def processed_file(
        self, new_text, filename, old_text=None, write=False, encoding=None
    ):
        """
        Called when a file has been refactored and there may be changes.
        """
        self.files.append(filename)
        if old_text is None:
            old_text = self._read_python_source(filename)[0]
            if old_text is None:
                return
            equal = old_text == new_text
            self.print_output(old_text, new_text, filename, equal)
            if equal:
                self.log_debug("No changes to %s", filename)
                if not self.write_unchanged_files:
                    return
                if write:
                    self.write_file(new_text, filename, old_text, encoding)
                else:
                    self.log_debug("Not writing changes to %s", filename)

    def write_file(self, new_text, filename, old_text, encoding=None):
        """Writes a string to a file.
        
        It first shows a unified diff between the old text and the new text, and
        then rewrites the file; the latter is only done if the write option is
        set.
        """
        try:
            f = _open_with_encoding(filename, "w", encoding=encoding)
        except OSError as err:
            self.log_error("Can't create %s: %s", filename, err)
            return

        try:
            f.write(_to_system_newlines(new_text))
        except OSError as err:
            self.log_error("Can't write %s: %s", filename, err)
        finally:
            f.close()

        self.log_debug("Wrote changes to %s", filename)
        self.wrote = True

    PS1 = ">>> "
    PS2 = "... "

    def refactor_docstring(self, input, filename):
        """Refactors a docstring, looking for doctests.
        
        This returns a modified version of the input string.  It looks
        for doctests, which start with a ">>>" prompt, and may be
        continued with "..." prompts, as long as the "..." is indented
        the same as the ">>>".
        
        (Unfortunately we can't use the doctest module's parser,
        since, like most parsers, it is not geared towards preserving
        the original source.)
        """
        result = []
        block = None
        block_lineno = None
        indent = None
        lineno = 0
        for line in input.splitlines(keepends=True):
            lineno += 1
            if line.lstrip().startswith(self.PS1):
                if block is not None:
                    result.extend(
                        self.refactor_doctest(block, block_lineno, indent, filename)
                    )
                block_lineno = lineno
                block = [line]
                i = line.find(self.PS1)
                indent = line[:i]
            elif indent is not None:
                if (
                    line.startswith(indent + self.PS2)
                    or line == indent + self.PS2.rstrip() + "\n"
                ):
                    block.append(line)
            else:
                if block is not None:
                    result.extend(
                        self.refactor_doctest(block, block_lineno, indent, filename)
                    )
                block = None
                indent = None
                result.append(line)

        if block is not None:
            result.extend(self.refactor_doctest(block, block_lineno, indent, filename))
        return ("").join(result)

    def refactor_doctest(self, block, lineno, indent, filename):
        """Refactors one doctest.
        
        A doctest is given as a block of lines, the first of which starts
        with ">>>" (possibly indented), while the remaining lines start
        with "..." (identically indented).
        
        """
        try:
            tree = self.parse_block(block, lineno, indent)
        except Exception as err:
            if self.logger.isEnabledFor(logging.DEBUG):
                for line in block:
                    self.log_debug("Source: %s", line.rstrip("\n"))

            self.log_error(
                "Can't parse docstring in %s line %s: %s: %s",
                filename,
                lineno,
                err.__class__.__name__,
                err,
            )
            return block

        if self.refactor_tree(tree, filename):
            new = str(tree).splitlines(keepends=True)
            clipped, new = new[: lineno - 1], new[lineno - 1 :]
            if not clipped == ["\n"] * (lineno - 1):
                raise AssertionError(clipped)
            if not new[-1].endswith("\n"):
                new[(-1)] += "\n"
            block = [indent + self.PS1 + new.pop(0)]
            if new:
                block += [indent + self.PS2 + line for line in new]
        return block

    def summarize(self):
        if self.wrote:
            were = "were"
        else:
            were = "need to be"
        if not self.files:
            self.log_message("No files %s modified.", were)
        else:
            self.log_message("Files that %s modified:", were)
            for file in self.files:
                self.log_message(file)

        if self.fixer_log:
            self.log_message("Warnings/messages while refactoring:")
            for message in self.fixer_log:
                self.log_message(message)

        if self.errors:
            if len(self.errors) == 1:
                self.log_message("There was 1 error:")
            else:
                self.log_message("There were %d errors:", len(self.errors))
            for msg, args, kwds in self.errors:
                self.log_message(msg, *args, **kwds)

    def parse_block(self, block, lineno, indent):
        """Parses a block into a tree.
        
        This is necessary to get correct line number / offset information
        in the parser diagnostics and embedded into the parse tree.
        """
        tree = self.driver.parse_tokens(self.wrap_toks(block, lineno, indent))
        tree.future_features = frozenset()
        return tree

    def wrap_toks(self, block, lineno, indent):
        """Wraps a tokenize stream to systematically modify start/end."""
        tokens = tokenize.generate_tokens(self.gen_lines(block, indent).__next__)
        for type, value, (line0, col0), (line1, col1), line_text in tokens:
            line0 += lineno - 1
            line1 += lineno - 1
            yield (type, value, (line0, col0), (line1, col1), line_text)

    def gen_lines(self, block, indent):
        """Generates lines as expected by tokenize from a list of lines.
        
        This strips the first len(indent + self.PS1) characters off each line.
        """
        prefix1 = indent + self.PS1
        prefix2 = indent + self.PS2
        prefix = prefix1
        for line in block:
            if line.startswith(prefix):
                yield line[len(prefix) :]
            else:
                if line == prefix.rstrip() + "\n":
                    yield "\n"
                else:
                    raise AssertionError("line=%r, prefix=%r" % (line, prefix))
                prefix = prefix2

        while True:
            yield ""


class MultiprocessingUnsupported(Exception):
    pass


class MultiprocessRefactoringTool(RefactoringTool):
    def __init__(self, *args, **kwargs):
        super(MultiprocessRefactoringTool, self).__init__(*args, **kwargs)
        self.queue = None
        self.output_lock = None

    def refactor(self, items, write=False, doctests_only=False, num_processes=1):
        if num_processes == 1:
            return super(MultiprocessRefactoringTool, self).refactor(
                items, write, doctests_only
            )
            try:
                import multiprocessing
            except ImportError:
                raise MultiprocessingUnsupported

            if self.queue is not None:
                raise RuntimeError("already doing multiple processes")
            self.queue = multiprocessing.JoinableQueue()
            self.output_lock = multiprocessing.Lock()
            processes = [
                multiprocessing.Process(target=self._child)
                for i in range(num_processes)
            ]
            try:
                for p in processes:
                    p.start()

                super(MultiprocessRefactoringTool, self).refactor(
                    items, write, doctests_only
                )
            finally:
                self.queue.join()
                for i in range(num_processes):
                    self.queue.put(None)

                for p in processes:
                    if p.is_alive():
                        p.join()

                self.queue = None

    def _child(self):
        task = self.queue.get()
        while task is not None:
            args, kwargs = task
            try:
                super(MultiprocessRefactoringTool, self).refactor_file(*args, **kwargs)
            finally:
                self.queue.task_done()

            task = self.queue.get()

    def refactor_file(self, *args, **kwargs):
        if self.queue is not None:
            self.queue.put((args, kwargs))
        else:
            return super(MultiprocessRefactoringTool, self).refactor_file(
                *args, **kwargs
            )
